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Summary of the impact

Veterinarians have long recognised health problems associated with
in-breeding and extreme
conformation in various pedigree dogs. However, the `Pedigree Dogs
Exposed' documentary in
2008, which particularly featured the plight of Cavalier King Charles
Spaniels (CKCS), and
resultant independent inquiry reports, to which RVC contributed, brought
the extent and severity of
the issue into the public eye. RVC's ongoing programme of research linked
to interaction with
stakeholders has contributed to the changes in breed standards instituted
by the Kennel Club (KC);
understanding of underlying principles governing the relationship between
structure and function
and affecting desired traits; developing tools to address
conformation-related health problems; and
driving changes in breeding practice leading to healthier dogs.

Underpinning research

Dr Clare Rusbridge, a veterinary neurologist now working in private
referral practice, was largely
responsible for bringing the problem of Chiari-like malformation and
syringomyelia (CM/SM) in
CKCS to light: publishing with RVC colleagues and others a paper which
first described
syringomyelia secondary to deformity of the caudal fossa and overcrowding
of the foramen
magnum [1]. This was sparked by her observation, whilst at the RVC
(1994-1997 as Senior
Training Scholar and then Staff Clinician), of a syndrome of persistent
scratching in CKCS, which,
through correspondence with general practitioners, was shown to be common
in the breed. Studies
at RVC continued to characterise the anatomical basis of the syndrome [2]
suggesting over-crowding of the caudal cranial fossa (CCF) occurred. More
recently, Dr Holger Volk (progressing
from internship and residency from 2004, to Senior Lecturer in Veterinary
Neurology and
Neurosurgery), together with Dr Imelda McGonnell (from 2004, Lecturer and
then Senior Lecturer
in Reproduction and Development), in collaboration with Rusbridge clearly
demonstrated that the
syndrome in CKCS was related to oversize of the cerebellum relative to the
CCF. Although clinical
signs do not correlate with degree of cerebellar herniation [3], the
presence of SM is related to the
size of the cerebellum leading to over-crowding of the caudal part of the
CCF [4].

Most recently, the research team has linked this to continuance of
juvenile appearance and traits
into adulthood, particularly of gait, which is known to be controlled by
the cerebellum (to be
published shortly). As the puppyish characteristics are viewed as major
part of their appeal, this
presents a real challenge to modifying the breed. The Animal Welfare team
has undertaken
sociological studies which are addressing similar issues of breed appeal
and (un)awareness of
health and welfare issues: for example, documenting the lack of perception
of breathing problems
(including Brachycephalic Obstructive Airway Syndrome (BOAS)) in
brachycephalic breeds [5].
This appreciation has helped the team in their interactions with owners
and breeders, to encourage
implementation of impact, and led to further research support from the
Cavalier breed Club.

To assist the KC's commitment to qualitative changes in breed
descriptors, to address breed-related
problems, Dr Charlotte Burn, (Research Fellow from 2008 and Lecturer in
Animal Welfare
Science since 2010) set out to quantify conformation-related problems
(slipped discs in long bodies
[6]; and eye ulcers and breathing disorders in brachycephalics (submitted
for publication 2013)),
with the aim of adding quantitative limits to KC breed standards.

The CKCS and other breed health issues have connected to several other
programmes of
research at RVC, for instance into mitral valve disease — where the
prevalence in CKCS is about
twenty times that of other breeds (see case study `Improving diagnosis and
treatment of canine
heart disease'). The need for quality data on prevalence and risk to
identify the true scale of health
issues, was a further concern highlighted in the inquiry reports triggered
by the Pedigree Dogs
Exposed documentary.

The RVC's VetCompass project, led by David Church (Professor of Small
Animal Studies since
2001) and Dr David Brodbelt (Lecturer from 2004, then Senior Lecturer in
Companion Animal
Epidemiology from 2007), is now addressing this need. The database has
grown to over 500,000
cases and has brought 180 private and charitable practices in the UK into
participation in the
research activity. One example of its use was a study using the (then) 89
primary veterinary clinics
supplying data, to analyse prevalence, risk factors and survival from
records of chronic kidney
disease — again quantifying the higher risk in certain breeds — in 107,214
dogs [7].

Other Quality and Relevance Indicators

McGonnell. The Development of Occipital Hypoplasia (Chiari-like
malformation) and syringomyelia
in the Cavalier King Charles spaniel. £7,500. 2007-8. Cavalier King
Charles Spaniel Club.

McGonnell and Volk. The development of Chiari-like malformation in the
CKCS. £9,000. 2010-13.

Details of the impact

In 2008, RVC contributed to the BBC1 documentary, Pedigree Dogs
Exposed, which attracted 3.9
million viewers, and was responsible for three separate reports being
commissioned into breed
issues [a]. The programme highlighted, principally, a welfare concern, but
noted additional
economic impact, in added costs of veterinary care. It reported that
pedigree animals make up
75% of the seven million dogs in the UK (estimated in 2012 to be 9.4
million) and cost their owners
over £10m in veterinarians' fees each week. The chronic pain affecting
CKCS afflicted by
syringomyelia was presented as a particularly graphic illustration of a
more general issue, and the
writer and director, acknowledged the substantial contribution from RVC
researchers to produce
the programme and subsequently: "I made particular use of RVC work on
Chiari-like Malformation
and Syringomyelia in Cavalier King Charles Spaniels [...] RVC
researchers and research findings
were also extremely helpful in preparation of the follow-up documentary,
in 2012, which reported
progress but also ongoing concerns over these two [with BOAS] welfare
issues. Amongst the
breakthrough developments since the original programme, I would single
out VetCompass for
providing the UK-wide epidemiological data necessary to monitor canine
health and welfare [...]
research originating from the Royal Veterinary College underpinned much
of the content of
Pedigree Dogs Exposed, ensuring the programme's claims could not be
dismissed lightly.
Furthermore, the lasting impact of the programme is due in no small part
to the College's continued
commitment to this issue." [b].

The first documentary was highly influential: resulting in the withdrawal
of coverage for Crufts dog
show by the BBC and termination of support by the Dogs Trust, the Royal
Society for the
Prevention of Cruelty to Animals and the People's Dispensary for Sick
Animals.

RVC's research and expertise was used in each of the resulting inquiry
reports [c,d,e], The reports
also noted a lack of quality data on prevalence of breed related health
problems. The Executive
Summary in the report of the Associate Parliamentary Group for Animal
Welfare noted: "However,
there is a lack of information available about the scale of the problem
[health and welfare of many
pedigree dogs], which makes it difficult to obtain a clear picture of
what percentage of dogs are
affected. As the Royal Veterinary College (RVC) has shown that the
problem is widespread to
different degrees of severity in many of the most popular breeds we
believe further action must be
taken immediately." The Bateson inquiry included a call for
evidence, and in the report, points from
respondents included: "A long list of heritable diseases affected dogs,
but little or no hard data
were available on prevalence. A few respondents pointed to the need for
a system to collect data
from veterinary surgeries, as being developed by the Royal Veterinary
College."

Each of the reports [c,d,e] concluded that current breeding practices
were detrimental to the
welfare of pedigree dogs. The Kennel Club subsequently completed its
ongoing revision of its
breed standards for every breed individually [f]. The revisions specify
that standards "will not
include anything that could in any way be interpreted as encouraging
features that might prevent a
dog from breathing, walking and seeing freely". For individual
breeds, the revisions frequently
include addition of `relatively', `moderately', `no exaggeration' and `not
excessive' and deletion of
`massive', to descriptions of breed characteristics. Additionally, it
sought to limit inbreeding by
"refusing to register those puppies that are born from any mother/son,
father/daughter or
brother/sister mating, taking place on or after 1st
March 2009". The Kennel Club's Genetics and
Health Information Manager acknowledges RVC's role: "RVC's research
into both the causes and
extent of breed-associated ill health and the extent of human perception
of these conditions, has
been extremely valuable in raising awareness and increasing
understanding of health and welfare
matters. Its work with breeders and breed clubs internationally has
helped to ensure that the
research outputs are taken into account and deliver tangible benefit in
terms of a healthier dog
population." [g]

An independent Advisory Council for welfare issues of dog breeding was
established in 2010, with
the support of the Dogs Trust, to pursue implementation of the other
recommendations of the three
reports [h]. Their Veterinary Director notes: "RVC... contributed to
the section [of the first annual
report] relating to breathing difficulties and the majority of the other
priorities (ocular problems,
syringomyelia, idiopathic epilepsy and heart disease) are areas in which
RVC research findings are
contributing to canine health and welfare." [i].

The perceived `demonisation' of specialist breeders, and their initial
rejection of the PDE
documentary's claims, themselves created a barrier to improving welfare.
Consequently, the RVC
researchers have pursued a positive relationship with the pedigree clubs,
guided by outputs from
research into owners' (limited) perceptions of problems. They have
developed partnerships with
associations representing CKCS and other affected breeds, aided by the
Kennel Club's
overarching support for liaison between breeders and veterinary
scientists, in order to involve them
actively in work designed to improve health and welfare. Outputs from
VetCompass have
assisted, as anticipated by the inquiry reports, in providing firm
evidence for scale and scope of
specific problems.

The number of CKCS in the UK alone is estimated to easily exceed 65,000
(over 11,000 are now
registered in a single year), making it the 6th most popular
breed. There are also breed clubs
across Europe, North America, South Africa, Australia and New Zealand. All
are said to be
descended from six dogs. Studies of relatively small selected groups
suggest that over 95% bear
the Chiari-like malformation and, the majority of these may go on to
develop SM. Other disorders
in CKCS consequent on in-breeding are, unsurprisingly, common.

CKCS breeders' symposia, attracting around 60-70 participants were held
in 2006 and 2010 and
led to the Cavalier Club sponsoring research at RVC (see [2,3]), relating
to the mismatch of brain
and cranium size in CKCS. [text removed for publication]. Interim breeding
guidelines were
instituted, based on the research, discussion and report from the
international Cavalier Club round
table organised and hosted by RVC in 2006 [j]. Five years on from this,
independent research
showed a tangible impact on dog health and welfare: where a scheme was
implemented to screen
dogs by MRI. Where it was possible to select at least one parent that was
SM-free at five years of
age, the incidence of young dogs with severe clinical symptoms was
reduced. The analysis
showed 70% of CKCS offspring were unaffected by SM when both parents SM
free; 77% were
affected when one parent affected; and 92% affected when both parents
affected. The publication
also commented: "One encouraging observation was that the proportion of
grade E (SM-affected
younger than 2.5 years of age) dropped from an average of 15 dogs per
year in years 2004 to
2006 to 11 dogs per year in years 2007 to 2009, that is, the breeding
guidelines may be achieving
the goal of reducing the risk of early onset SM, however, this
hypothesis would be needed to be
tested in a more vigorous study" [k]. A Kennel Club/BVA health
screening scheme for Chiari Mal-formation/Syringomyelia
in multiple breeds based on this pilot scheme was introduced in 2012 [l].

Thus work has progressed from demonstrating in-bred and conformational
health problems, to
highlighting the on-going ignorance of their effects [m], and involvement
by the research team of
breeders, owners and veterinarians, to determine the scale and specifics
of problems to drive
change in breeding practices.